There is another report from Balticon XXX April 1996 by Pam Korda whwhere she states that RJ "said something that implied that the die and live again prophecy-fulfillment was the lightning incident in The Fires of Heaven, and not the hanging incident in The Shadow Rising".

However, there is a direct interview from 1999, with the following Q&A:


Here RJ rather implies that the hanging was the fulfillment, but in the end he uses RAFO. This makes clear that the reports from 1996 probably also didn't got definite answers, but were just misinterpretations by the posters.

As said, BS indicates as well that the hanging was the fulfillment, and he knows the notes.

It actually also would make sense, because in the balefire incident Mat never died. Besides that, the whole Prophecy states: "To die and live again, and live once more a part of what was". The last part obviously refers to the old memories Mat got from the Eelfinn. But Mat already began to use these memories immediately after the hanging incident, not only after the balefire incident. Thus, it's more likely that the hanging fulfilled the Prophecy.